Improvement in scroll-sawing machines



H. LAWRENCE. Scroll Sawing-Machine s.

Patented May 13, 1873.

UNITED STATES PATENT OFFIoE.

HUMPHREY LAWRENCE, OF FREDERIOTON, CANADA.

IMPROVEMENT IN SCROLL-SAWING MACHINES.

Specification forming part of Letters Patent No. 138,808, dated May 13, 1873; I application filed March 25, 1873. i

1'0. all whom it may concern:

Be it known that I, HUMPHREY LAWRENCE, of the city of Fredericton, in the county of York and Province of New Brunswick, Dominion of Canada, have invented certain new and useful Improvements in Scroll- Sawing Machines; and hereby declare that the following is a full, clear, and exact description thereof, that will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawing and to the letters of reference marked thereon which form a part of this specification.

My invention consists of the frame A, metallic arms B, tension-rod O, pivotal balance D, plates E and E, saw-frame F, guides b and b, adjustable catches H and H, foot G, treadle Y, driving-wheel J, pulley K, and saw-pitman L, and the combination and arrangement thereof, substantially as shown and described.

In the accompanying drawing, which illustrates my invention and forms a part of the specification thereof, Figure 1 is a side elevation of the sawing-machine. Fig. 2 is a front view of plate marked E, detached. Fig. 3 is a view of the spring-catch, detached. Fig. 4 is a back view of pivotal balance, detached.

A is the frame of my device, and consists of the upright standards A, the lateral pieces a, and the longitudinal pieces a. B represents two metallic arms, which are rigidly attached to the frame at B, and which converge toward the face or plates E and E, to which they are rigidly attached, or they may be cast solid therewith. The plate E has therein a vertical slot wherein plays the forked arm f, which indirectly connects the saw-frame and saw N. The forked arm or elbow f is composed of two metallic elbow-shaped pieces of metal, which are united at the apex thereof and pivoted to the saw-frame at f while the flaring arms or elbows f are rigidly attached to the holder, one on opposite sides thereof, thus forming an indirect connection between the saw N and the saw-frame F. The thimble h is a circular or nearly circular piece of metal embracing the adjuster h, the ends thereof projecting horizontally therefrom and furnishing bearings for the adjustable spring-catch H. The adjuster h is a piece of cylindrical metal,

which is rigidly attached to the saw-rod T. Said adjuster has provided therein vertical slots a short distance beneath the apex thereof, and into said slots or recesses the tooth of the catch is securely held by the spring P, which impinges in the slot or recess aforesaid, and prevents the thimble h from becoming de tached from the slide. The adjuster is pro vided with a number of said slots or recesses on the periphery thereof, which are located at regular intervals corresponding with similar slots provided at like intervals on the adjuster It. By this arrangement it is obvious that when it is desirable to turn the teeth of the saw in'a given line radiating from its center, it is only necessary to depress the springcatches p, whereupon the saw is released, and

can be conveniently turned, as aforesaid. G is a foot, which is attached to the plate E and held rigidly in position by the combined setscrew and nut-lock g. Said foot is designed to rest upon and hold in proper position the material while it is being operated upon by the saw. E is a metallic plate, which is provided with a vertical slot, and also with the disk 0, which latter is rigidly attached to the table immediately beneath thev same. The saw-rods T are round bars of iron, having therein vertical slits or incisions for the reception of the respective ends of the saw-blade. The saw-blade is rigidly attached to the bars by pins, which project horizontally through said bars, as shown. Said saw-rods play in the guides 11 b and thimbles h h and the saw is held in the desired position by the catches H and H, in connection with the slide, the tooth of the catch being held securely in vertical slots or recesses provided in the adjuster h and when it is desirable to revolve the saw within the guides it can be accomplished by depressing the springs p, as aforesaid, and thus lifting the tooth of the catch from the slots or recess aforesaid. f is a forked arm, pivoted to the thimble h at one end; and con necting with the horizontal piece Z at its opposite or lower end. Said horizontal piece Z is rigidly attached to the saw-frame at Z.'

The pivotal balance D is composed of the horizontal axle d d and the vertical bars d, which latter support and brace the upper and nether arms of the saw=frame. The bearings of the axle d cl are metallic, and rest in shoulders provided respectively on the apex *of the standards A. The tension-rod 0 passes vertically through the saw-frame F, and a washer is pressed upon the upper arm of said frame by the combined nut-lock and wrench W. Y is a treadle for operating the device. X is a a frame for the power or balance-wheel and pulley K, the shaft of the power-wheel resting in the metallic bearings u, and the shaft of the pinion also resting in metallic bearings. The

belting a connects the power-wheel J with the pulley K. The crank L, which indirectly connects and operates the lower end of the saw and saw-frame, is jointed at l, a bolt being passed vertically through the saw-frame and through the cap, and another bolt horizontally beneath the said cap 1 Claim. 

